1. Field of the Invention
This invention relates generally to the field of internal combustion engines, and more particularly to two-stroke internal combustion engines.
2. Description of the Prior Art
U.S. Pat. No. 1,292,322 is directed to a water cooled two cycle gas engine provided with a dual walled cylinder having a lower, rotatably mounted perforated valve member for gas entry and accuated by a first cam and spring/rocker arm arrangement. Gases exhaust through an upper reciprocating sleeve valve member controlled by a cam movably connected to the shaft to the cylinder's piston connecting rod is also connected.
U.S. Pat. No. 1,540,286 relates to an internal combustion piston engine provided with exhaust valves located in the upper portion of the cylinder. The engine is also provided with either a rotary gas inlet or a crankcase gas inlet valve communicating with a crankcase gas pressuring chamber.
U.S. Pat. No. 2,337,245 discloses an internal combustion engine of the two stroke type having a set of gas inlet ports at one end of the cylinder and a set of gas exhaust ports at the other cylinder end. Each set of gas ports is opened and closed by means of a separate reciprocating piston which is positioned in the cylinder.
U.S. Pat. No. 2,516,708 relates to a single-acting two-stroke cyclic internal cobustion engine having an associated air scavenging chamber adjacent to the gas inlet end of the cylinder.
U.S. Pat. No. 2,572,768 also relates to a two-stroke internal combustion engine having gas inlet ports providing swirling motion by tangential gas injection arrangements.
U.S. Pat. No. 4,004,557 discloses a piston-cylinder assembly having a cup-like upper extension of the piston, and a plurality of vertical passages between the crankcase and the cylinder.